TTS Bench — Speed — mac-default

Rig: mac-m4 — Apple M4 (10C) · Apple M4 GPU (MPS) · 16 GB RAM · Darwin 25.5.0

Label: default voice

TTFA = time to first audio (ms; lower is better). RTF = real-time factor (× realtime; higher is better; e.g. 10× means 10 sec of audio generated per 1 sec of compute). Cold = first run after process start; warm = subsequent runs.

Speed winners

Fastest predefined-voice: Piper (cpu) — 32.14× warm RTF, 208ms warm TTFA

Fastest cloning-capable: Pocket-TTS (cpu) — 7.82× warm RTF, 44ms warm TTFA

Model	Device	TTFA cold	TTFA warm	RTF cold	RTF warm	Peak RAM	Peak VRAM	Size	Released
Piper	cpu	228ms	208ms	27.47×	32.14×	561 MB	—	~25MB	Jan 2023
Kokoro	mps	920ms	489ms	7.58×	15.28×	1.26 GB	—	82M	Dec 2024
MeloTTS	mps	1.88s	512ms	4.09×	15.13×	1.55 GB	—	~52M	Feb 2024
Kokoro (MLX) (4/5 ok)	mps	2.10s	514ms	3.90×	14.88×	774 MB	—	82M	—
Kokoro	cpu	914ms	749ms	7.78×	10.04×	2.49 GB	—	82M	Dec 2024
KittenTTS Nano 0.1	cpu	994ms	1.01s	8.10×	8.08×	385 MB	—	<100M	Aug 2025
Pocket-TTS	cpu	89ms	44ms	7.50×	7.82×	1.69 GB	—	100M	Jan 2026
Soprano 1.1 80M	cpu	912ms	906ms	7.15×	7.15×	1.18 GB	—	80M	Jan 2026
MeloTTS	cpu	2.35s	1.27s	3.20×	6.48×	3.30 GB	—	~52M	Feb 2024
Soprano 1.1 80M	mps	2.48s	1.30s	2.76×	5.16×	1.64 GB	—	80M	Jan 2026
Supertonic 3	cpu	1.86s	1.57s	4.18×	4.81×	968 MB	—	99M	May 2026
StyleTTS 2	cpu	5.94s	2.21s	2.30×	3.82×	3.13 GB	—	~148M	Jun 2023
NeuTTS Nano	cpu	740ms	266ms	2.30×	3.10×	5.83 GB	—	229M	Dec 2025
NeuTTS Nano	mps	1.45s	464ms	1.81×	2.96×	1.28 GB	—	229M	Dec 2025
NeuTTS Air	cpu	1.38s	358ms	1.55×	2.16×	6.12 GB	—	748M	Sep 2025
NeuTTS Air	mps	2.32s	583ms	1.30×	2.08×	1.55 GB	—	748M	Sep 2025
Coqui XTTS-v2	mps	17.81s	7.82s	1.14×	1.70×	1.84 GB	—	750M	Oct 2023
Chatterbox Turbo	mps	9.95s	5.07s	0.75×	1.44×	2.30 GB	—	744M	Dec 2025
Coqui XTTS-v2	cpu	6.01s	5.48s	1.41×	1.43×	4.61 GB	—	750M	Oct 2023
Voxtral 4B TTS	mps	6.45s	6.37s	1.12×	1.19×	1.93 GB	—	4B	Nov 2025
Chatterbox Turbo	cpu	6.53s	6.45s	1.07×	1.14×	4.80 GB	—	744M	Dec 2025
VibeVoice Realtime 0.5B	mps	9.56s	8.30s	0.98×	1.13×	838 MB	—	0.5B	Dec 2025
OmniVoice	mps	8.05s	12.20s	0.81×	0.79×	1.38 GB	—	~1B	Mar 2026
OmniVoice	cpu	12.84s	11.28s	0.49×	0.57×	3.59 GB	—	~1B	Mar 2026
Magpie-TTS	cpu	25.55s	26.19s	0.40×	0.40×	4.69 GB	—	357M	Dec 2025
Parler-TTS Mini v1	cpu	25.23s	22.58s	0.32×	0.39×	8.60 GB	—	878M	Jun 2024
Chatterbox	cpu	18.77s	17.08s	0.33×	0.37×	4.83 GB	—	1.2B	Apr 2025
VibeVoice Realtime 0.5B	cpu	25.45s	25.10s	0.38×	0.36×	3.17 GB	—	0.5B	Dec 2025
Chatterbox	mps	25.95s	31.35s	0.27×	0.29×	698 MB	—	1.2B	Apr 2025
Qwen3-TTS 1.7B Base	cpu	24.52s	25.11s	0.25×	0.24×	3.93 GB	—	1.7B	Jan 2026
Sesame CSM-1B	cpu	38.67s	31.30s	0.19×	0.24×	6.08 GB	—	1B	Mar 2025
VoxCPM2 2B	cpu	28.36s	52.13s	0.29×	0.17×	144 MB	—	2B	Apr 2026
IndexTTS-2	cpu	80.00s	48.40s	0.08×	0.14×	318 MB	—	1.5B	Jun 2025
F5-TTS v1	mps	45.43s	45.54s	0.09×	0.09×	1.29 GB	—	330M	Oct 2024
F5-TTS v1	cpu	47.26s	47.15s	0.09×	0.09×	3.31 GB	—	330M	Oct 2024
VibeVoice 1.5B (2/4 ok)	cpu	71.46s	70.84s	0.05×	0.06×	9.01 GB	—	1.5B	Aug 2025
OuteTTS 1.0 1B (2/5 ok)	mps	121.18s	93.13s	0.04×	0.05×	733 MB	—	1B	Apr 2025
OuteTTS 1.0 1B (2/5 ok)	cpu	100.71s	95.88s	0.05×	0.05×	7.38 GB	—	1B	Apr 2025
LuxTTS	cpu	LuxTTS install failed (piper-phonemize has no Windows wheels)
LuxTTS	mps	LuxTTS install failed (piper-phonemize has no Windows wheels)
ZipVoice 123M	cpu	Reference wav missing for voice cloning
ZipVoice 123M	mps	Reference wav missing for voice cloning
Mars5-TTS	cpu	Timed out after 10 min — model too slow at this prompt length
VibeVoice 1.5B	mps	Skipped — out of memory (model exceeds available RAM)

Model

Device

TTFA cold

TTFA warm

RTF cold

RTF warm

Peak RAM

Peak VRAM

Size

Released

Piper

cpu

228ms

208ms

27.47×

32.14×

561 MB

—

~25MB

Jan 2023

Kokoro

mps

920ms

489ms

7.58×

15.28×

1.26 GB

—

82M

Dec 2024

MeloTTS

mps

1.88s

512ms

4.09×

15.13×

1.55 GB

—

~52M

Feb 2024

Kokoro (MLX) (4/5 ok)

mps

2.10s

514ms

3.90×

14.88×

774 MB

—

82M

—

Kokoro

cpu

914ms

749ms

7.78×

10.04×

2.49 GB

—

82M

Dec 2024

KittenTTS Nano 0.1

cpu

994ms

1.01s

8.10×

8.08×

385 MB

—

<100M

Aug 2025

Pocket-TTS

cpu

89ms

44ms

7.50×

7.82×

1.69 GB

—

100M

Jan 2026

Soprano 1.1 80M

cpu

912ms

906ms

7.15×

1.18 GB

—

80M

Jan 2026

MeloTTS

cpu

2.35s

1.27s

3.20×

6.48×

3.30 GB

—

~52M

Feb 2024

Soprano 1.1 80M

mps

2.48s

1.30s

2.76×

5.16×

1.64 GB

—

80M

Jan 2026

Supertonic 3

cpu

1.86s

1.57s

4.18×

4.81×

968 MB

—

99M

May 2026

StyleTTS 2

cpu

5.94s

2.21s

2.30×

3.82×

3.13 GB

—

~148M

Jun 2023

NeuTTS Nano

cpu

740ms

266ms

2.30×

3.10×

5.83 GB

—

229M

Dec 2025

NeuTTS Nano

mps

1.45s

464ms

1.81×

2.96×

1.28 GB

—

229M

Dec 2025

NeuTTS Air

cpu

1.38s

358ms

1.55×

2.16×

6.12 GB

—

748M

Sep 2025

NeuTTS Air

mps

2.32s

583ms

1.30×

2.08×

1.55 GB

—

748M

Sep 2025

Coqui XTTS-v2

mps

17.81s

7.82s

1.14×

1.70×

1.84 GB

—

750M

Oct 2023

Chatterbox Turbo

mps

9.95s

5.07s

0.75×

1.44×

2.30 GB

—

744M

Dec 2025

Coqui XTTS-v2

cpu

6.01s

5.48s

1.41×

1.43×

4.61 GB

—

750M

Oct 2023

Voxtral 4B TTS

mps

6.45s

6.37s

1.12×

1.19×

1.93 GB

—

Nov 2025

Chatterbox Turbo

cpu

6.53s

6.45s

1.07×

1.14×

4.80 GB

—

744M

Dec 2025

VibeVoice Realtime 0.5B

mps

9.56s

8.30s

0.98×

1.13×

838 MB

—

0.5B

Dec 2025

OmniVoice

mps

8.05s

12.20s

0.81×

0.79×

1.38 GB

—

~1B

Mar 2026

OmniVoice

cpu

12.84s

11.28s

0.49×

0.57×

3.59 GB

—

~1B

Mar 2026

Magpie-TTS

cpu

25.55s

26.19s

0.40×

4.69 GB

—

357M

Dec 2025

Parler-TTS Mini v1

cpu

25.23s

22.58s

0.32×

0.39×

8.60 GB

—

878M

Jun 2024

Chatterbox

cpu

18.77s

17.08s

0.33×

0.37×

4.83 GB

—

1.2B

Apr 2025

VibeVoice Realtime 0.5B

cpu

25.45s

25.10s

0.38×

0.36×

3.17 GB

—

0.5B

Dec 2025

Chatterbox

mps

25.95s

31.35s

0.27×

0.29×

698 MB

—

1.2B

Apr 2025

Qwen3-TTS 1.7B Base

cpu

24.52s

25.11s

0.25×

0.24×

3.93 GB

—

1.7B

Jan 2026

Sesame CSM-1B

cpu

38.67s

31.30s

0.19×

0.24×

6.08 GB

—

Mar 2025

VoxCPM2 2B

cpu

28.36s

52.13s

0.29×

0.17×

144 MB

—

Apr 2026

IndexTTS-2

cpu

80.00s

48.40s

0.08×

0.14×

318 MB

—

1.5B

Jun 2025

F5-TTS v1

mps

45.43s

45.54s

0.09×

1.29 GB

—

330M

Oct 2024

F5-TTS v1

cpu

47.26s

47.15s

0.09×

3.31 GB

—

330M

Oct 2024

VibeVoice 1.5B (2/4 ok)

cpu

71.46s

70.84s

0.05×

0.06×

9.01 GB

—

1.5B

Aug 2025

OuteTTS 1.0 1B (2/5 ok)

mps

121.18s

93.13s

0.04×

0.05×

733 MB

—

Apr 2025

OuteTTS 1.0 1B (2/5 ok)

cpu

100.71s

95.88s

0.05×

7.38 GB

—

Apr 2025

LuxTTS

cpu

LuxTTS install failed (piper-phonemize has no Windows wheels)

LuxTTS

mps

LuxTTS install failed (piper-phonemize has no Windows wheels)

ZipVoice 123M

cpu

Reference wav missing for voice cloning

ZipVoice 123M

mps

Reference wav missing for voice cloning

Mars5-TTS

cpu

Timed out after 10 min — model too slow at this prompt length

VibeVoice 1.5B

mps

Skipped — out of memory (model exceeds available RAM)